problem using freestylesvg
As far as I know, Freestyle SVG Export is meant exclusively as a stroke export solution, for the freestyle part of the render only

It is not a full featured rendered solution, for backgrounds and diffuse colors, nor would it even be possible to reliably export the whole rendered output as an SVG file.

I am pretty sure if you tweak the settings of the SVG file in an external editor like Inkscape or any other vector graphics editor capable of opening or importing an SVG file, you can easily achieve the look you are aiming for.



For an alternative solution check out the excellent SVG Output Script